The digital hacking group known as Lulz Security says it has disbanded.

The group gained international prominence for its ability to breach websites of the U.S. Central Intelligence Agency, Sony Corporation, the U.S. Senate and a prominent British police unit.

Lulz Security gave no reason for the decision to end its website hacking activity, which was announced Saturday on Twitter. But it is under investigation by law enforcement agencies in the United States, Britain and elsewhere.

Early last week, British police arrested a 19-year-old man on suspicion of involvement with Lulz Security.

In what appeared to be a final act, the group released a collection of plundered documents from the U.S. telecom company AT&T, an Irish detective agency and Internet company America On-Line.

“Our planned 50-day cruise has expired,” Lulz Security said it its announcement. “We must now sail into the distance.”